A resin molded product for a material of a model such as a master model or a mock-up model is supplied as a model or a mold, after being formed into an arbitrary shape by cutting or grinding.
In recent years, because of various conditions such as a decrease in the number of wooden patternmakers, improvement in computers, the requirement for a shortened delivery period of model production, etc., model production by cutting or grinding with an NC (numerical control) machine has become a major method.
The dust generated when cutting or grinding a resin molded product for material of a model by an NC machine causes contamination of the working environment. Thus, the amount of generated dust may be reduced by a method in which liquid with a low chemical activity such as an ester compound or an ether compound in which the hydroxyl groups at both ends of a (poly)oxyalkylene compound, e.g. a polyalkylene glycol, are blocked with a fatty acid or a higher alcohol, is included in a resin (Publication of International Patent Application WO 98/17703).
However, this method may lead to a reduction in the strength of the material, and a finished model may be damaged or deformed easily. Therefore, although this method can be applied to a material of a mock-up model that may have relatively low strength, it may not be desirable to apply this method to a material of a master model or a mold that requires strength.
As a result of intensive investigation to solve the above problem, the inventors have found that by including microcapsules containing an encapsulated material in a liquid state into a resin composition, it is possible to obtain a resin molded product for material of a model, in which the amount of dust generated by cutting or grinding is small and a decrease in the strength is small. Thus, the present invention has been accomplished.